Retinal Architecture, Intrathecal Immunity, and Clinical Course in Multiple Sclerosis
Published online May 1, 2017
Knier et al. assessed potential relationships between retinal volume, immunologic variables in the cerebrospinal fluid, and the course of disability in patients with relapsing-remitting multiple sclerosis (MS). They found that atrophy of the retinal ganglion cell layer correlates with elevated intrathecal B-cell fractions and is a strong independent risk factor for worsening disability. In addition, a thicker inner nuclear layer indicated enhanced brain activity on magnetic resonance imaging (MRI).
For this observational study, the researchers evaluated 312 adults who were treated at the same hospital. Patients in cohort 1 (n = 72) had very early disease (i.e., first relapse within 3 months of study entry). Patients in cohort 2 (n = 240) had disease duration of at least 12 months at study baseline. All underwent optical coherence tomography (OCT) and MRI. The primary outcome variable was confirmation of worsening disability.
For cohort 1, volumes of the common ganglion cell–inner plexiform layer (GCIPL) and the inner nuclear layer (INL) were compared with immunoglobulin indices and the frequency of immune cells in cerebrospinal fluid to detect potential associations. Volume of the GCIPL itself (for both cohorts) or the GCIPL corrected for intrathecal B-cell frequencies (cohort 1) was examined in relation to disability course.
In cohort 1, low GCIPL volume was associated with greater frequency of intrathecal B cells and with intrathecal immunoglobulin G synthesis. INL volume correlated with the quantity of intrathecal CD56bright natural killer cells (r = 0.28; p = .007). Low GCIPL volume (≤ 1.99 mm3) denoted a 6.4-fold risk for worsening disability in cohort 1 and a 2.4-fold risk in cohort 2 (versus higher volumes). For both cohorts, INL volume correlated with subsequent increases in gadolinium-enhancing lesions and the T2 lesion load.
In conclusion, GCIPL loss is an independent risk factor for worsening disability in relapsing-remitting multiple sclerosis. OCT of the retina may help determine the most appropriate treatment for each patient.
The original article can be found here.